There is now considerable evidence that both cellular and non-cellular components of the dermis exert significant influence on epidermal cell differentiation, epidermal-dermal adhesion, and normal development of skin basement membrane. Furthermore, aberrations within the dermis and/or basement membrane may lead to the clinical findings associated with several blistering diseases of the skin; most notably epidermolysis bullosa (EB). Within the past few years artificial dermal biomatrices have been produced and successfully used as substrates for growth and at least partial differentiation of epidermal cells; further technological improvements in this field undoubtedly will have great impact on the future treatment of burns and ulcerative diseases of the skin. In addition, such reconstituted skin may be potentially used to establish long awaited models for diseases such as EB. Unfortunately, to date the dermal biomatrices which have been produced lack close biochemical similarity to normal intact dermis, thereby potentially limiting their long term usefulness as artificial skin or as models of particular disease states. The first objective of this study is to develop a biochemically and physiologically more natural dermal biomatrix by reconstitution of human fibroblasts with purified native human matrix constituents (collagen types I, III, V, and VI; fibronectin; dermal proteoglycans) found in intact human dermis. Second, several purified basement membrane components will be added to the biomatrix surface prior to the addition of epidermal cells, so as to assess the functional roles and influences of such constituents on the reconstituted skin. Third, recombinant skin equivalents will be prepared using the optimized dermal biomatrix and cells from patients with EB. These latter recombinants will then be evaluated in vitro by immunological, biochemical, and morphological means and in vivo as xenographs in order to critically assess the influence of fibroblasts, epidermal cells, and extracellular matrix constituents in each of the forms of EB and ultimately establish a realistic laboratory model for this disease.